The Ring of Fire: A guide to Earth's most powerful geological forces

Stretching for nearly 25,000 miles in a horseshoe shape that encircles the Pacific Ocean, the Ring of Fire is home to some of the most powerful, awe-inspiring and deadly forces seen on our dynamic planet.

The fierce geologic energies that gave the region its ominous name account for nearly 90 percent of the world's earthquakes. The region is also home to nearly three-quarters of all the world's volcanoes, both active and dormant.

"It's not for nothing that it's called the Ring of Fire," USGS Cascades Volcano Observatory volcanologist John Ewert said, referring to the hundreds of volcanoes that dot Pacific coastlines and snake around the western seas from South America to Oceania.

More than 450 volcanoes can be found in the Ring of Fire and were spawned by the slow and intense pressures of continental plate movements deep beneath the Earth's surface.

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What is the driving force behind the region's earthquake activity?

The deadliest tsunami event in history occurred as a result of the 2004 Indian Ocean earthquake, which registered at a 9.1 magnitude.

The colossal tsunami generated by the quake claimed nearly 230,000 lives across 15 nearby countries. In 2011, another devastating tsunami struck Japan after a powerful earthquake originated off the Japanese coastline.

These types of events are caused by plate interactions at subduction zones, or megathrusts, where oceanic plates converge and slide underneath continental plates.

"It happens about as fast as your fingernails grow," Ewert said, referring to the slow, drawn-out process of plate subduction.

Converging plates are strongly locked, slowly building their energy over an extended period of geologic time. When the pressures become too great, the locked plates violently rupture and create powerful earthquakes at their boundaries.

Where does the fire originate?

In addition to causing earthquakes, the same slow processes of converging plates have also created the region's towering mountain ranges and the hundreds of stratovolcanoes that make up the Ring of Fire's volcanic arcs, Ewert added.

"Central American volcanoes are, for the most part, a different type of volcano than those that we study and monitor in Hawaii," USGS Hawaiian Volcano Observatory Spokeswoman Janet Babb said.

"They lie along a plate boundary, formed by subduction of two convergent plates, whereas Hawaiian volcanoes overlie a hot spot and are formed by a mantle plume."

Unlike shield volcanoes, which are created by hot spots, stratovolcanoes are steep, conical volcanoes that were built by the eruption of viscous lava flows and pyroclastic flows, according to the USGS.

Ewert compared these types of volcanic interactions originating deep under the waves to a lava lamp where the intense pressures and heat from the plate movements create magma.

Like in a lava lamp, magma ascends to the surface. If the heat and gases of the magma buildup are intense enough, a volcanic eruption will occur.

"There are [approximately] 80 volcanic eruptions each year," Ewert said, adding that while many volcanic eruptions seem to occur simultaneously at different points in the Ring of Fire, this is a result of the dynamic system at work.

"In a larger sense, it is all part of one system."

Ewert said that there are many active and dormant volcanoes in the Ring of Fire, and that a volcano can remain dormant for hundreds or even thousands of years, before reactivating and going through another period of activity.

"We're humans and only live about 70 to 80 years," he said. "These are systems that are hundreds of thousands of years old."